Tahoe snowpack third-lightest since 1981

See a comparison between this year's and last year's snow pack.
Jason Bean

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Jeff Anderson, a hydrologist for the United States Dept. of Agriculture, records data while doing a snow survey near the top of Mt. Rose Highway near Reno on Dec. 28, 2017.(Photo: Jason Bean/RGJ)Buy Photo

The winter of 2017-18 is off to a slow start in the Sierra Nevada, a stark contrast from the record-busting snow totals last year.

The contrast from last year is particularly evident in the Lake Tahoe Basin where winter is off to its third-driest start since 1980-81.

Snow survey results posted Thursday show the basin is at 30 percent of normal for the date, compared to 67 percent on the same date last year.

The Mt. Rose Snotel site on Slide Mountain reported 36 inches of snow with 11 inches of water content, which is 84 percent of normal. On the same date last year, the site had 58 inches of snow and was at 119 percent of normal.

“We are behind where we were last year at this time,” said Jeff Anderson, a hydrologist from the Nevada Natural Resources Conservation Service, a federal agency that tracks snow in the west.

In the short-term, the dry December isn’t expected to have much effect on the water supply for the Reno-Tahoe region. That’s because the heavy precipitation last year filled reservoirs, including Lake Tahoe, to the brim.

“Even if we have a fairly dry year we can still maintain the targeted flows,” said Chad Blanchard, federal water master in Reno.

The slow start to winter is, however, a reminder that drought remains a concern for the region.

“While it’s too early to know for sure if this will be a drought year, we had better start acting as though drought was going to be a normal, not abnormal, part of western water’s future,” said Peter Gleick, co-founder of the Pacific Institute, an Oakland-based global water think tank.

Snowpack in the Truckee River Basin is at 59 percent of normal. It’s at 50 and 64 percent of normal in the Carson and Walker river basins.

Great Basin ranges are also drier than normal. Eastern Nevada is at 31 percent of normal for the year, Clover Valley and the Upper Humboldt basins near Elko are at 42 and 44 percent. The Lower Humboldt basin is at 38 percent.

It’s an even drier story in California.

According to the California Department of Water Resources, the northern Sierra is at 24 percent of normal, the central Sierra is at 33 percent and the southern Sierra is at 23 percent.

“We have a really poor snowpack now, but if we get in a storm track that can change rapidly,” Anderson said.

The dryness is particularly noticeable below 8,000 feet, where the snowpack is just 25 percent of normal for the date.

The Snotel at Ward Creek near Tahoe City is at the lowest it has ever been recorded on this date in 39 years of data. A Snotel at 7,600 feet at Rubicon reported its second-lowest level ever and another station at 7,880 feet at Marlette Lake showed the fourth-lowest level on record for the date.

It happened last year, too, albeit with more overall snow. At this time last year snow levels above 8,000 feet were near or above normal. Below 8,000 feet they were as much as 40 percent below normal.

“That is exactly what we expect from climate change,” Gleick said. “The snowline will move up because it is warmer.”

Gleick said the changing climate means winters that were once considered typical for the Sierra Nevada are increasingly rare. And conditions once considered extreme are increasingly likely.

That means communities should shift their behavior to conserve more water when available and learn to capture more water that arrives as rain. Currently much of the water capture and storage systems in California and the west are built to capture gradual snowmelt.

“All of those decisions about reservoir management are based on old 20th century statistics,” Gleick said. “If there is anything we have learned from climate change it is that those statistics aren’t valid anymore.”